Course 5 week 2 assignment 2 submit error

Although I finished all the exercises but when I click the button ‘Submit Assignment’ , it replied the score 0/100


I have passed all the tests
test 1:

test 2:
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test 3:
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test 4:

test 5:

Passing the unit tests does not mean your code is perfect. The unit tests don’t check for every possible error in your code.

Perhaps in one of your functions, you’re using an index value that is out-of-range for the unit test the grader uses.